Blade driving device for high resolution imaging apparatus

ABSTRACT

To enable continuous operational control of the blade member with high resolution and good accuracy, even when achieving miniaturization and thickness reduction in a blade driving device, through enabling smooth movement of a movable member in a blade driving device. A blade driving device  1  comprises: a base member  2  that has an opening  2 A; one or a plurality of blade members  3  that operate so as to advance into the opening  2 A or withdraw from the opening  2 A; a driving member  4  that moves within a plane that is perpendicular to the optical axis that passes through the opening  2 A, to drive the blade member  3 ; and supporting members  7  that are provided between the base member  2  and the driving member  4 , so as to provide sliding support or elastic support of the driving member  4  in a state that is separated from the base member  2.

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.15/553,931 filed Aug. 25, 2017, which is a U.S. national phaseapplication under 35 U.S.C. § 371 of International Patent ApplicationNo. PCT/JP2016/055765, filed Feb. 26, 2016, and claims benefit ofpriority to Japanese Patent Application No. 2015-039575, filed Feb. 27,2015; Japanese Patent Application No. 2015-074383, filed Mar. 31, 2015;and Japanese Patent Application No. 2015-074384, filed Mar. 31, 2015;Japanese Patent Application No. 2015-074385, filed Mar. 31, 2015;Japanese Patent Application No. 2015-090750, filed Apr. 27, 2015; andJapanese Patent Application No. 2015-090752, filed Apr. 27, 2015;Japanese Patent Application No. 2015-102182, filed May 19, 2015;Japanese Patent Application No. 2015-128507, filed Jun. 26, 2015;Japanese Patent Application No. 2015-179912, filed Sep. 11, 2015; andJapanese Patent Application No. 2015-183797, filed Sep. 17, 2015. Theentire contents of these applications are hereby incorporated byreference.

FIELD OF TECHNOLOGY

The present invention relates to a blade driving device used in animaging device, or the like.

BACKGROUND

In an imaging device, or the like, a blade driving device is provided soas to function so as to block light (a shutter function), to adjust thebrightness, to be an optical filter, or the like, in front of a focusingoptics system. Conventionally, the blade driving device comprises a baseplate (a substrate) that has an opening, one or more blade members thatslide on the base plate to cover the opening, and an operating mechanismfor opening and closing the blade member, and a driving source, such asan electromagnetic actuator, is provided in the operating mechanism.

The blade driving device functions as that which blocks like (ashutter), that which adjusts the brightness, as optical filter, or thelike, provided as the stage prior to focusing more a focusing opticssystem in, for example, a photodetecting unit or a camera unit(including an imaging device), and is driven by an actuator toopen/close blade a member in relation to an opening through which lightpasses, to fully open/fully close the opening, or to adjust the area ofthe opening.

Use of a linear motor as an actuator for a blade driving device is known(referencing Japanese Unexamined Patent Application Publication2001-281724). A linear motor is provided with a magnet that is securedto one member, of a stationary base and a driving member for driving ablade member, or secured to the other member thereof, to drive thedriving member within a plane (linear driving) through anelectromagnetic driving force that is produced when an electric currentis applied to the coil.

SUMMARY

In a conventional blade driving device, a movable member, such as ablade member, is supported on a base plate that has an opening, and whenthe movable member is moved along the base plate by opening or closingof an operating mechanism, there is a problem in that the movable membercannot be moved smoothly due to friction because of the surface contactof the movable member. Because of this, in the actuating mechanism ofthe blade driving device, it is necessary to have an actuator thatgenerates a relatively large torque in order to open and close the blademember, and thus there is a problem in that this increases the size ofthe actuator, preventing the blade driving device as a whole from beingsufficiently thin.

Moreover, there is the need for control that not only switches theopening/closing state of the blade member between two states, that is,the open state and the closed state, but that also opens and closes theblade member in stages; however, in this case there is a problem in thatthe friction of the surface contact of the movable member makes a highlyaccurate control of the opening and closing difficult. In particular,because, of necessity, the driving stroke of the actuator must be smallin a blade driving device that is equipped in a camera unit that isinstalled in a mobile device, performing continuous blade memberoperational control with higher resolution during the small drivingstroke requires the ability to move more smoothly the movable memberthat includes the blade member.

Moreover, in the operating mechanism for a blade driving device, thedriving by the actuator is transmitted to the blade member throughanother member, and a mechanism is employed that amplifies the drivingstroke of the actuator and transmits it to the blade member, thatchanges the direction of the driving stroke of the actuator when movingthe blade member, or the like. In such operating mechanisms, linkingportions between different members are structured through, for example,elongated holes and shaft portions that are fitted therein, and it isnecessary to provide some degree of play in the fit therebetween.However, when there is such play in a linking portion, movement isproduced in the blade member caused by a change in the direction inwhich gravity acts, due to a change in orientation, or caused by camerashaking, or the like, and thus there is a problem in that thisinterferes with accurate control of the opening/closing state of theblade member.

Moreover, there is a strong demand for miniaturization and reduction ofthickness in, for example, photodetector units and camera units that areinstalled in the mobile electronic devices that have become so popularin recent years, requiring, of course, miniaturization and thicknessreduction in the blade driving devices that are equipped therein. On theother hand, there is a demand for high-speed and high-resolution controlunit controlling the opening in the blade driving device, and anadequately strong driving force is required in the actuator in order toachieve such control.

The blade driving device that uses a linear motor as an actuator, asdescribed above, is able to produce a reduction in thickness, but, inorder to increase the driving force, requires a plurality of actuatorsthat are equipped with coils and magnets. In a conventional bladedriving device, the driving force has been increased through distributedplacement of such actuators. When the driving force of the actuators isincreased through such distributed placement, there is a problem in thatthis is incompatible with the need for miniaturization, due to theincrease in the space required for installing the actuators.

Because mobile electronic devices are driven primarily by batteries,there is the need to reduce as far as possible the electric powerconsumed by the actuators in the mobile electronic device. In regards tothis, with distributed placement of actuators, as described above, theconsumption of electric power is not always efficient, despite theability to increase the driving force. When a blade driving device isinstalled in a mobile electronic device, there is the need both toimprove the driving force and to conserve electric power, throughefficient consumption of electric power.

In the present invention, the handling of such problems is an example ofthe problem to be solved. That is, objects of the present invention areto enable continuous operational control of blade members with highresolution and good accuracy, to prevent play in the linking portionbetween members, to enable accurate control of the opening/closing stateof the blade member, and the like.

Moreover, another object of the present invention is a reduction inthickness, and to achieve both an improvement in the driving force andconservation of electric power, through the provision of an actuatorthat is capable of an adequate driving force wherein high-speed andhigh-resolution opening control is possible in a blade driving device.

In order to achieve such an object, the blade driving device accordingto the present invention is provided with the following structures:

A blade driving device comprising: a base member that has an opening;one or a plurality of blade members that operates so as to advance intothe opening or withdraw from the opening; and a driving member thatmoves within a plane that is perpendicular to an optical axis thatpasses through the opening, to drive the blade member, or that is theblade member itself, wherein: the driving member is supported in a statewherein it is separated from the base member.

A blade driving device comprising: a base member that has an opening;one or a plurality of blade members that operates so as to advance intothe opening or withdraw from the opening; and a driving member thatmoves within a plane that is perpendicular to an optical axis thatpasses through the opening, to drive the blade member, wherein: thedriving member is supported on the base member in a state wherein thedriving member is separated from the base member, and the driving memberis connected to the blade member through a connecting member, where alinking portion, for preventing connection play, is provided between thedriving member and the connecting member.

A blade driving device comprising: a base member that has an opening;one or a plurality of blade members that operates so as to open andclose the opening; and a driving member that moves within a plane thatis perpendicular to an optical axis that passes through the opening todrive the blade member; along with a driving source for the drivingmember, configured from a coil that is provided on one member, of thebase member and the driving member, and a magnet that is provided on theother member, of the base member and the driving member, wherein: themagnet comprises a unit magnetized portion that is magnetized along theoptical axial direction; and in the coil, a coil portion that has a pairof linear parts that produces a driving force through the application ofan electric current is disposed over the magnet, where two linear partshaving identical directions for the directions with which the electriccurrent is applied are disposed in relation to at least one unitmagnetized portion.

Because in the blade driving device according to the present invention,having the distinctive features described above, the driving member fordriving the blade member is supported in a state that is separate fromthe base member, the movable members in the blade driving device can bemoved smoothly, enabling continuous operational control of the blademember to be carried out with high resolution and good accuracy, evenwhen achieving miniaturization and thickness reduction of the bladedriving device.

Moreover, this enables control of the state of opening/closing of theblade member with good accuracy, through preventing play in the linkingportions between members in the blade driving device.

The blade driving device is provided with a driving source that producesa driving force that is adequate to enable high-speed andhigh-resolution opening control, enabling miniaturization and areduction in thickness. Moreover, this enables achievement of both animprovement in the driving force and conservation of electric power.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 2 (a) is an explanatory diagram depicting a plan view of an exampleof a blade driving device according to an example according to thepresent invention.

FIG. 2(b) is an explanatory diagram depicting a side view of an exampleof a blade driving device according to an example according to thepresent invention.

FIG. 3 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 4 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 5 is a plan view depicting an example of a blade driving deviceaccording to an example according to the present invention.

FIG. 6(a) is explanatory diagrams depicting a plan view of the structurefor holding the rolling element.

FIG. 6(b) is an explanatory diagram depicting a cross-sectional view ofthe structure for holding the rolling element.

FIG. 6(c) is an explanatory diagram depicting another cross-sectionalview of the structure for holding the rolling element.

FIG. 7(a) is an explanatory diagrams depicting a cross-sectional view ofthe structure for holding the rolling element.

FIG. 7(b) is an explanatory diagram depicting another cross-sectionalview of the structure for holding the rolling element.

FIG. 8 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 9 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 10 is a plan view depicting an example of a blade driving deviceaccording to an example according to the present invention.

FIG. 11 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 12 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 13 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 14 is a plan view depicting an example of a blade driving deviceaccording to an example according to the present invention.

FIG. 15 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 16(a) is an explanatory diagrams depicting a screw-type example ofanother configuration for a driving member in a blade driving deviceaccording to an example according to the present invention.

FIG. 16(b) is an explanatory diagram depicting a cam type example ofanother configuration for a driving member in a blade driving deviceaccording to an example according to the present invention.

FIG. 17 is an exploded perspective diagram depicting an example of ablade driving device equipped with the driving member depicted in FIG.16 .

FIG. 18 is a plan view of the assembled state of FIG. 17 .

FIG. 19 is an exploded perspective diagram depicting an example of ablade driving device equipped with the driving member depicted in FIG.16 .

FIG. 20 is an exploded perspective diagram depicting an example of ablade driving device equipped with the driving member depicted in FIG.16 .

FIG. 21 is an exploded perspective diagram depicting an example of ablade driving device equipped with the driving member depicted in FIG.16 .

FIG. 22 is an exploded perspective diagram depicting an example of ablade driving device equipped with the driving member depicted in FIG.16 .

FIG. 23 is an explanatory diagram depicting a camera unit equipped witha blade driving device according to an example according to the presentinvention.

FIG. 24 is an explanatory diagram (an exploded perspective diagram) ofan example wherein an operating lever (a connecting member) is provided.

FIG. 25(a) is an explanatory diagram of an example wherein an operatinglever (a connecting member) is.

FIG. 25(b) is an explanatory diagram of an example wherein an operatinglever (a connecting member) is provided in a state wherein the openingis closed.

FIG. 26(a) is an explanatory diagram of an example wherein an operatinglever (a connecting member) is provided.

FIG. 26(b) is an explanatory diagram of an example wherein an operatinglever (a connecting member) is provided in a state wherein the openingis closed.

FIG. 27 is an explanatory diagram (an exploded perspective diagram) ofan example wherein an operating lever (a connecting member) is provided.

FIG. 28 is an explanatory diagram (a plan view) of an example wherein anoperating lever (a connecting member) is provided.

FIG. 29 is an explanatory diagram (a partial enlarged view) of anexample wherein an operating lever (a connecting member) is provided.

FIGS. 30(a) and (b) are graphs depicting the effects when elastic memberis provided in the connecting portion (the linking portion). WhereinFIG. 30(a) is a case wherein the elastic member is not provided, andFIG. 30(b) is a case wherein the elastic member is provided.

FIG. 31 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 32 is an explanatory diagram (a partial enlarged view) of anexample wherein an operating lever (a connecting member) is provided.

FIG. 33 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 34 is a plan view depicting an example of a blade driving deviceaccording to an example according to the present invention.

FIG. 35 is a cross-sectional view depicting an example of a bladedriving device according to an example according to the presentinvention.

FIG. 36 is an exploded perspective diagram depicting an example of ablade driving device according to an example according to the presentinvention.

FIG. 37 is a plan view depicting an example of a blade driving deviceaccording to an example according to the present invention.

FIG. 38(a) is an explanatory diagram illustrating a plan view of anexample configuration of a driving source in the blade driving device(wherein (a) is a plan view explanatory diagram, and (b) is across-sectional view along X-X thereof).

FIG. 38(b) is an explanatory diagram illustrating a cross-sectional viewalong X-X thereof of an example configuration of a driving source in theblade driving device.

FIG. 39(a) is an explanatory diagrams illustrating an exampleconfiguration of a two unit magnetized portion driving source in a bladedriving device.

FIG. 39(b) is an explanatory diagram illustrating an exampleconfiguration of a three unit magnetized portion driving source in ablade driving device.

FIG. 39(c) is an explanatory diagram illustrating an exampleconfiguration of a three unit magnetized portion driving source in ablade driving device.

FIG. 39(d) is an explanatory diagram illustrating an exampleconfiguration of a four unit magnetized portion driving source in ablade driving device.

FIG. 40 is an explanatory diagram depicting an example configuration ofa driving source in the blade driving device.

FIG. 41(a) is an explanatory diagrams depicting other exampleconfigurations of driving sources in the blade driving device depictedin FIG. 39 (c).

FIG. 41(b) is an explanatory diagram depicting other exampleconfigurations of driving sources in the blade driving device depictedin FIG. 39 (d).

FIG. 42 is an explanatory diagram depicting an example configuration ofa driving source in the blade driving device.

FIG. 43(a) is a cross-sectional explanatory diagrams depictingpositional relationships between back yokes and magnets, with which thedriving means for the blade driving device are.

FIG. 43(b) is a planar explanatory diagram depicting positionalrelationships between back yokes and magnets, with which the drivingmeans for the blade driving device are equipped.

FIG. 44(a) is a cross-sectional explanatory diagrams depictingpositional relationships between back yokes and magnets, with which thedriving means for the blade driving device are equipped.

FIG. 44(b) is a planar explanatory diagram depicting positionalrelationships between back yokes and magnets, with which the drivingmeans for the blade driving device are equipped.

FIG. 45(a) is a cross-sectional explanatory diagrams depictingpositional relationships between back yokes and magnets, with which thedriving means for the blade driving device are equipped.

FIG. 45(b) is a planar explanatory diagram depicting positionalrelationships between back yokes and magnets, with which the drivingmeans for the blade driving device are equipped.

FIG. 46(a) is a cross-sectional explanatory diagrams depictingpositional relationships between back yokes and magnets, with which thedriving means for the blade driving device are equipped.

FIG. 46(b) is a planar explanatory diagram depicting positionalrelationships between back yokes and magnets, with which the drivingmeans for the blade driving device are equipped.

FIG. 47(a) is a cross-sectional explanatory diagrams depicting exampleswherein the driving member is held on the base member through a springforce.

FIG. 47(b) is a planar explanatory diagram depicting examples whereinthe driving member is held on the base member through a spring force.

FIG. 48(a) is a cross-sectional explanatory diagrams depicting anexample of detecting means for the blade driving device.

FIG. 48(b) is a planar explanatory diagram depicting an example ofdetecting means for the blade driving device.

FIG. 49(a) is an explanatory diagrams depicting an example of detectingmeans in a blade driving device.

FIG. 49(b) is an explanatory diagram depicting an example of detectingmeans in a blade driving device wherein a coil is used for driving.

FIG. 50(a) is an explanatory diagrams depicting a specific exampleconfiguration for the operating lever (the connecting member).

FIG. 50(b) is an explanatory diagram depicting a cross-sectional viewalong the section X-X thereof of a specific example configuration forthe operating lever (the connecting member).

FIG. 51 is an explanatory diagram depicting a camera unit equipped witha blade driving device according to an example according to the presentinvention.

FIG. 52 is an explanatory diagram depicting a mobile electronic devicein which is equipped a camera unit comprising a blade driving deviceaccording to an example according to the present invention.

DETAILED DESCRIPTION

Examples according to the present invention will be explained below inreference to the drawings. In the explanations below, identicalreference symbols are assigned for identical positions in the differentdrawings, and redundant explanations are omitted. In the variousdrawings, the optical axial direction is defined as the Z direction, anaxial direction within a plane that is perpendicular to the optical axisis defined as the X direction, and the direction that is perpendicularto the X direction within the plane that is perpendicular to the opticalaxis is defined as the Y direction.

In FIG. 1 and FIG. 2 , the blade driving device 1 comprises a basemember 2, a blade member 3, a driving member 4, and a supporting member7. The base member 2 has an opening 2A, and is a member that supportsthe driving member 4. In the example in the figures, the base member 2comprises a base plane 20 that has an opening 2A, and a side wall 21that surrounds the outer periphery of the base plane 20. Here theoutside shape of the base member 2 is rectangular, but there is nolimitation to being rectangular, and may instead be another shape, suchas a circular shape, or the like.

The blade member 3 may be provided singularly, or in a pluralitythereof, and is a member that operates so as to to advance into theopening 2A or withdraw from the opening 2A. In the example in thefigure, a pair of blade members 3A and 3B is provided, where the twoblade members 3A and 3B overlap each other over the opening 2A, and areadjusted variably in order to change continuously the area through whichlight passes through the opening 2A.

The driving member 4 is a member that moves within a plane (the X-Y)that is perpendicular to the optical axis that passes through theopening 2A (for example, the axis of the opening 2A), to drive the basemember 3, and refers to either the actuator itself, or to a drivingelement of the actuator. The driving member 4 may be structured from amember other than the blade member 3, or may be structured from theblade member 3 itself.

While in the explanation below the driving member 4 is described as anelectromagnetic actuator that is driven linearly, there is no limitationthereto, but rather, for example, any of a variety of types of drivingsources may be used, such as, for example, a piezoelectric actuator, anelectromagnetic plunger, or the like. In the example illustrated in FIG.1 , the driving source is a linearly driven electromagnetic actuatormade from a magnet 5 and a coil 6, where the driving member 4 is amovable element that is able to move along a plane (the X-Y plane), andcomprises a driving frame 40 and the magnet 5 that is held on thedriving frame 40. While here an example is depicted wherein the drivingmember 4 is a pair of driving members 4A and 4B (a plurality of drivingsources), and a plurality of magnets 5 is held on each of the drivingframes 40, a single driving source may be provided instead.

Coils 6 for electromagnetically driving the driving member 4 are held oncoil holding members 60, as illustrated in the figure, or are secureddirectly to the base member 2. In the example in the figure, the coilholding member 60, whereon a coil 6 is held, is provided with a securinghole 60A, where the coil holding member 60 is secured to the base member2 through fitting the securing hole 60A onto a securing protrusion 20Ethat is provided on the base plane 20.

The coils 6 are disposed corresponding to the magnets 5 of the drivingmember 4, where the driving member 4 is moved along an axial direction(for example, the X direction in the figures) within the plane (the X-Yplane) through application of an electric current to the coils 6. Theapplication of the electric current to the coils 6 is carried outthrough a flexible circuit board 11 that is mounted on the base member2.

Here the supporting members 7 are provided between the base member 2 andthe driving member 4, to support slidably the driving member 4 in astate wherein it is separated from the base member 2. While here anexample is depicted wherein the driving member 4 is supported slidablyin a state wherein it is separated from the base member 2, the drivingmember 4 may instead be supported elastically in a state wherein it isseparated from the base member 2. The driving member 4 is supportedrelative to the base member 2 through supporting members 7, and drivesthe blade member 3 so as to move within a plane (the X-Y plane) that isperpendicular to the optical axis (the axis of the opening 2A) thatpasses through the opening 2A.

In such a blade driving device 1, the driving member 4 is supported bysupporting members 7 in a state wherein the driving member 4 isseparated from the base member 2, so that the driving member 4 can moverelative to the base member 2 without a large frictional resistance.Through this, the movable members of the blade driving device 1 are ableto move smoothly, enabling a reduction in size and weight of the drivingmember 4 through enabling a reduction in the driving force, enabling theblade driving device 1 itself to be made smaller and thinner. Moreover,even when the blade driving device 1 has been made smaller and thinner,the movement of the movable members is smooth, enabling continuousoperational control of the blade member 3 to be carried out with highresolution and good accuracy.

The example illustrated in FIG. 1 and FIG. 2 will be explained ingreater detail. In the base member 2, supporting grooves 20A areprovided in a plurality of locations on the base plane 20. Thesupporting grooves 20A are grooves that extend in the X direction andwhich have triangular or trapezoidal cross-sections, where a rollingelement (a spherical body) 7A, which is a supporting member 7, issupported in each individual supporting groove 20A. Moreover, a shaft20B is provided on the base plane 20 so as to support the blade member 3and the driving member 4 so as to be able to move.

The supporting grooves 20A have directionality that guides the drivingmember 4, so that the driving member 4 moves along the supportinggrooves 20A. The supporting grooves 20A, in the example in the figure,are provided linearly, and thus the driving member 4 is able to movewith linear motion; however, there is no limitation thereto, but ratherthe supporting grooves 20A may be provided in a curve, enabling thedriving member 4 to undergo rotational movement along a curved path.

The driving member 4 moves along the supporting grooves 20A that areprovided on the base member 2, and thus the driving member 4 can becaused to move with stability, guided by the supporting grooves 20A.Moreover, the directionality (a straight line or a curve) of thesupporting grooves 20A may be set arbitrarily, making it possible to setthe movement of the driving member 4 to an arbitrary direction.

Coils 6 that are connected to a flexible circuit board 11 are supported,either directly or through coil holding members 60, on the base plane 20of the base member 2. In the driving member 4, magnets 5 are held on aplate-shaped driving frame 40, and supporting grooves 40A are formed inpositions in the driving frame 40 corresponding to the supportinggrooves 20A, described above. Moreover, in a state wherein thesupporting members 7 (the rolling elements 7A) are supported in thesupporting grooves 20A, when the driving member 4 is supported so as toface the base plane 20, the supporting members 7 (the rolling elements7A) are held between the supporting grooves 20A and supporting grooves40A, so that the driving member 4 is supported slideably in a state thatis separated from the base member 2. The supporting members 7 (rollingelements 7A) are caused to roll by the movement of the driving member 4,where the driving member 4 moves along the supporting grooves 20A and40A.

At this time, back yokes 12 are disposed at a position corresponding tothe magnets 5 that are supported on the driving frame 40, on the backface of the base member 2. The driving member 4 is drawn to the basemember 2 side through magnetic attraction between the back yokes 12 andthe magnets 5. The coils 6 are disposed in magnetic circuits formed fromthe magnets 5 and the back yokes 12. The existence of the supportingmembers 7 (the rolling elements 7A) causes the formation of magneticgaps, with a uniform spacing, between the magnets 5 and the base member2, and the coils 6 are disposed within these magnetic gaps.

The coils 6 have a pair of linear parts, where these pair of linearparts are disposed so as to face away from each other in the Y directionin the figures. In contrast, the magnets 5 are magnetized so as to formmagnetic flux that passes through the linear parts of the coils 6 in theZ direction. Through this, the driving frame 40 or the driving member 4,on which the magnets 5 are held, is biased by a driving force in the Xdirection.

In the example depicted in FIG. 1 and FIG. 2 , a pair of blade members 3(3A and 3B) is provided, and a pair of driving frames 40 for the drivingmembers 4 (4A and 4B) is provided corresponding to the blade members 3Aand 3B. Moreover, the blade member 3A is attached (directly) as a singleunit with the driving frame 40 of the driving member 4A, and the blademember 3B is attached (directly) as a single unit with the driving frame40 of the driving member 4B.

When an electric current is applied to the coils 6, the driving member 4is moved in the X direction along the supporting grooves 20A (or thesupporting grooves 40A) through Lorentz forces that are produced betweenthe coils 6 and the magnets 5, acting so as to move the pair of blademembers 3A and 3B in mutually opposing directions along the X direction.At this time, the driving member 4 is drawn toward the base member 2side, with the supporting members 7 therebetween, and thus the drivingmember 4 is driven with stability with a single plane, to move smoothly,with little resistance.

In the example in the drawings, the driving member 4 is disposed at aposition overlapping the blade member 3 on the periphery of the opening2A of the base member 2. This eliminates the need for the provision of adriving member 4 at a position that is separated from the blade member,making it possible to reduce the space for the installation area. Thedriving member 4 overlaps the blade member 3 at the periphery of theopening 2A, and is disposed over a relatively wide range. Through this,the magnets 5 can be located distributed around the opening 2A, enablingminiaturization of the individual magnets 5.

The base member 2 is configured so as to enable installation of a covermember 8 on the front end of a side wall 21. The cover member 8, whichhas an opening in 8A, covers the front face of the base member 2, toform an interior space S between the base member 2 and the cover member8. The blade member 3 and the driving member 4 are contained within thiscompact interior space S, and operate within a plane so as to adjust,with continuously variable adjustments, the area of the opening 2Athrough which light passes.

While FIG. 1 and FIG. 2 depict an example wherein the blade member 3 andthe driving member 4 operate as a single unit, the blade member 3 itselfmay instead hold the magnets 5, and the driving frame 40 may be omitted.Moreover, the blade member 3 and the driving member 4 may be separateunits, where the blade member 3 and the driving member 4 are coupledthrough an operating mechanism, so that the movement of the drivingmember 4 within the plane is relayed to the blade member 3 through theoperating mechanism.

FIG. 3 depicts an example of another form of the blade driving device 1.In this example, the driving member 4 is provided with a driving frame40 that is a single unit, where a plurality of magnets 5 is held on thedriving frame 40. This driving frame 40 is a ring-shaped memberconfigured so as to encompass the opening 2A, where a plurality ofmagnets 5 are disposed distributed on the periphery of the opening 2A.This driving frame 40 undergoes reciprocating motion in the axialdirection, along the X direction, when an electric current is applied tothe coils 6. In contrast, a bearing portion 10A of an operating lever 10that serves as the operating mechanism is born on a shaft 20C that isprovided on the base plane 20 of the base member 2. The other structuresare identical to those in the example in FIG. 1 .

In this case, a pair of blade members 3 (3A and 3B) is provided, with asingle driving frame 40, and an operating mechanism (an operating lever10) is provided to cause the pair of blade members 3A and 3B to move inmutually opposing directions through movement of the driving frame 40 ina single direction. That is, when the driving frame 40 moves in the Xdirection, one of the blade members 3A that is equipped on the drivingframe 40 moves in the same direction, and, simultaneously, one endportion 10X of the operating lever 10 moves in the identical directiontherewith. In contrast, the other end portion 10Y of the operating lever10 moves in the opposite direction of the one end portion 10X, rotatingaround the shaft 20C of the operating lever 10. This other end portion10Y is coupled to the other blade member 3B, moving the blade member 3Bin the direction opposite to that of the blade member 3A.

FIG. 4 and FIG. 5 depict an example of another form of the blade drivingdevice 1. In this example, the driving member 4 (driving frame 40) isprovided with holding grooves 40B for holding rolling elements(spherical bodies) 7A, as supporting members 7, so as to be able torotate at fixed positions. In this example, the rolling elements 7A thatare held in the holding grooves 40B roll on the supporting face 20D ofthe base plane 20, to support the driving member 4 (the driving frame40) slideably within a plane (the X-Y plane). The other structures inthe example depicted in FIG. 4 and FIG. 5 are identical to those in theexample depicted in FIG. 1 . Moreover, the configuration may be onewherein the holding grooves 40B in the example depicted in FIG. 4 arereplaced with the supporting grooves 40A in the example depicted in FIG.3 , with the supporting face 20D in the example depicted in FIG. 4replaced with the supporting grooves 20A in the example depicted in FIG.3 .

In the example depicted in FIG. 4 and FIG. 5 , as with the exampledepicted in FIG. 1 , an example is depicted wherein the blade member 3and the driving member 4 operate as a single unit; however the magnets 5may instead be held on the blade member 3 itself, and the driving frame40 may be omitted. Moreover, the blade member 3 and the driving member 4may be separate units, where the blade member 3 and the driving member 4are coupled through an operating mechanism, so that the movement of thedriving member 4 within the plane is relayed to the blade member 3through the operating mechanism.

FIG. 6 and FIG. 7 depict a structure for holding the rolling elements7A. As illustrated in FIG. 6 (b), the rolling element 7A may be providedwith a retaining portion 40B that has a recessed portion 7P in thedriving frame 40 on the driving member 4 side, so as to be held, so asto enable rolling, with the this recessed portion 7P (referencing FIG. 4and FIG. 5 ), and, as illustrated in FIG. 6 (c), may be provided with aretaining portion 20A1 that has a recessed portion 7P on the base member2 side, and may be held, so as to enable rolling, within this recessedportion 7P. The rolling elements 7A that are held in the retainingportions 40B and 20A1 move on the opposing supporting faces (planes) 20Dand 40A1.

In regards to holding of the rolling elements 7A, they may be heldthrough a plate member 7S, which has good slip performance, asillustrated in FIG. 7 . In this case as well, a retaining portion 40Bmay be provided in the driving frame 40 on the driving member 4 side, asdepicted in FIG. 7 (a), or a retaining portion 20A1 may be provided onthe base member 2 side, as depicted in FIG. 7 (b).

In such a blade driving device 1, the driving member 4 is supported byrolling elements 7A in a state wherein the driving member 4 is separatedfrom the base member 2, so that the driving member 4 can move relativeto the base member 2 without a large frictional resistance. Throughthis, the movable members of the blade driving device 1 are able to movesmoothly, enabling a reduction in size and weight of the driving member4 through enabling a reduction in the driving force, enabling the bladedriving device 1 itself to be made smaller and thinner. Moreover, evenwhen the blade driving device 1 has been made smaller and thinner, themovement of the movable members is smooth, enabling continuousoperational control of the blade member 3 to be carried out with highresolution and good accuracy.

FIG. 8 depicts an example of another form of the blade driving device 1.In this example, the driving member 4 (the driving frame 40) is providedwith bearings 40C, where rollers 7B are born, as the supporting members7, on the bearings 40C. The rollers 7B include axles 7B1 along the Ydirection, so as to enable the driving member 4 to move in the Xdirection, where the axles 7B1 are born on the bearings 40C. The rollers7B that are born by the bearings 40C roll on the supporting face 20D inthe base plane 20, to support the driving member 4 (the driving frame40) slideably within a plane (the X-Y plane). The other structures inthe example depicted in FIG. 8 are identical to those in the exampledepicted in FIG. 1 . Moreover, the configuration may be one wherein thebearings 40C and rollers 7B in the example illustrated in FIG. 8 arereplaced, respectively, with the supporting grooves 40A and rollingelements 7A of the example illustrated in FIG. 3 , and the supportingface 20D of the example illustrated in FIG. 8 is replaced with thesupporting grooves 20A of the example illustrated in FIG. 3 . Moreover,the bearings 40C and the rollers 7B in the example illustrated in FIG. 8may be replaced with the holding grooves 40B and the rolling elements 7Aof the example illustrated in FIG. 4 .

In the example depicted in FIG. 8 , as with the examples depicted inFIG. 1 and FIG. 4 , an example is depicted wherein the blade member 3and the driving member 4 operate as a single unit; however the magnets 5may instead be held on the blade member 3 itself, and the driving frame40 may be omitted. Moreover, the blade member 3 and the driving member 4may be separate units, where the blade member 3 and the driving member 4are coupled through an operating mechanism, so that the movement of thedriving member 4 within the plane is relayed to the blade member 3through the operating mechanism.

FIG. 9 and FIG. 10 depict an example of another form of the bladedriving device 1. In this example, shafts 7C that extend along the Xdirection within the plane (the X-Y plane) are provided as thesupporting members 7 on the base member 2, where the driving member 4(the driving frame 40) is provided with sliding portions 40D, wherethese sliding portions 40D are equipped so as to be able to slide on theshafts 7C. The shafts 7C are equipped on the base member 2 throughinsertion into fitting holes 20G that are provided in the base member 2.While here the shafts 7C are provided on the base member 2, the shafts7C may be provided on the driving member 4 side instead, with thesliding portions 40D provided on the base member 2 side.

The shafts 7C that are provided on the base member 2 have directionalityfor guiding the driving member 4, and the driving member 4 moves alongthe shafts 7C. The shafts 7C, in the example in the figure, are providedlinearly, and thus the driving member 4 is able to move with linearmotion; however, there is no limitation thereto, but rather the shafts7C may be provided in a curve, enabling the driving member 4 to undergorotational movement along a curved path.

The driving member 4 moves along the shafts 7C that are provided on thebase member 2, and thus the driving member 4 can be caused to move withstability, guided by the shafts 7C. Moreover, the directionality (astraight line or a curve) of the shafts 7C may be set arbitrarily,making it possible to set the movement of the driving member 4 to anarbitrary direction.

In this example as well, the driving member 4 is supported slideably onthe base member 2 by the supporting members 7 (the shafts 7C). Throughthe sliding portions 40D of the driving member 4 sliding along theshafts 7C, the driving member 4 is supported in a state wherein it isseparated from the base member 2, so as to be able to move along the Xdirection within the plane (the X-Y plane). The other structures in theexample depicted in FIG. 9 and FIG. 10 are identical to those in theexample depicted in FIG. 1 . Moreover, the configuration may be suchthat the supporting grooves 40A, the rolling elements 7A, and thesupporting grooves 20A of the example depicted in FIG. 3 replace thesliding portions 40D and shafts 7C of the example depicted in FIG. 9 andFIG. 10 , with the single unit driving frame 40 of the example depictedin FIG. 3 supported on the base member 2 by the shafts 7C so as to beable to move smoothly.

In the example depicted in FIG. 9 and FIG. 10 , as with the exampledepicted in FIG. 1 , FIG. 4 , and FIG. 8 , an example is depictedwherein the blade member 3 and the driving member 4 operate as a singleunit; however the magnets 5 may instead be held on the blade member 3itself, and the driving frame 40 may be omitted. Moreover, the blademember 3 and the driving member 4 may be separate units, where the blademember 3 and the driving member 4 are coupled through an operatingmechanism, so that the movement of the driving member 4 within the planeis relayed to the blade member 3 through the operating mechanism.

FIG. 11 is a modified example of the blade driving device depicted inFIG. 9 and FIG. 10 . In this example, as with the example depicted inFIG. 3 , the blade member 3 and the driving member 4 are attachedthrough another member (the operating lever 10), so that the blademember 3 undergoes rotational movement through the linear motion of thedriving member 4. The other structures are identical to those in theexample depicted in FIG. 9 and FIG. 10 . The coupling of the operatinglever 10 and the blade member 3 will be described below (in reference toFIG. 24 through FIG. 26 ).

Moreover, in the example depicted in FIG. 11 , an opening limitingmember 13 is provided in front of the opening 2A of the base member 2,where the opening area (the amount of exposure) when the blade member 3is fully open is limited accurately by an opening 13A of the openinglimiting member 13. Moreover, through the movement of the blade member3, described above, the blade members 3A and 3B will advance into, orwithdraw from, the opening 13A, so that the opening area of the opening13A (the amount of exposure) is adjusted variably with high accuracy.The opening limiting member 13 can be employed in all of the exampleconfigurations described above and example configurations describedbelow.

FIG. 12 depicts an example of another form of the blade driving device1. In this example, elastic members (springs) 7D are interposed, assupporting members 7, between the base member 2 and the driving member 4(the driving frame 40), so that the driving member 4 is supportedelastically on the base member 2 in a state wherein the driving member 4is separated from the base member 2. Here an example is illustratedwherein a single driving member 4A (4B) is supported elastically bythree elastic members 7D, where one end of the elastic member 7D issupported on a supporting portion 40E of the driving member 4 (thedriving frame 40), and the other end of the elastic member 7D issupported on a supporting portion 20F of the base member 2.

FIG. 12 depicts an example wherein springs are used for the elasticmembers 7D, but, as illustrated in FIG. 13 and FIG. 14 , wires, or thelike, that have bending elasticity and that have a reactive force forsupporting in the axial direction, may be used instead of the springs.The other structures in the example depicted in FIG. 12 through FIG. 14are identical to those in the example depicted in FIG. 1 . Moreover, theconfiguration may be one wherein the supporting portions 40E, theelastic members 7D, and the supporting portions 20F, depicted in FIG. 12through FIG. 14 , are replaced with the supporting grooves 40A, therolling elements 7A, and the supporting grooves 20A, in the examplesdepicted in FIG. 3 , and the single driving frame 40, depicted in FIG. 3, may be supported elastically on the base member 2 through the elasticmember 7D.

In this example, when an electric current is applied to the coils 6, thedriving member 4 moves straight in the X direction due to theapplication of a magnetic force through the Lorentz forces that areproduced between the coils 6 and the magnets 5, where this movementcauses the pair of blade members 3A and 3B to travel straight inmutually opposing directions in the X direction. At this time, thedriving member 4 is supported elastically within a plane that isperpendicular to the optical axis, and thus can move in the direction inwhich the magnetic force is applied. Given this, when the electriccurrent is stopped, the elastic force of restitution of the elasticmembers 7D returns the position of the driving member 4 to an arbitraryposition wherein there is an equilibrium with the magnetic force thatacts between the magnets 5 and the back yolks 12.

While in the example depicted in FIG. 12 and FIG. 13 an example isdepicted wherein the blade member 3 and the driving member 4 operate asa single unit, the blade member 3 itself may instead hold the magnets 5,and the driving frame 40 may be omitted. Moreover, if the blade member 3and the driving member 4 our separate units, then, as depicted in FIG.15 , the blade member 3 and the driving member 4 should be coupledthrough an operating lever 10 (an operating mechanism), so that themovement of the driving member 4 within the plane is relayed to theblade member 3 through the operating mechanism. In this case, the blademember 3 and the driving member 4 are connected through the operatinglever 10, so that the blade member 3 will undergo rotational motionthrough the linear motion of the driving member 4.

In the blade driving devices 1 in the various example configurations setforth above, the driving members 4 are supported on the base members 2through the supporting members 7, where the driving members 4 aresupported slideably or supported elastically, separated from the basemember 2, enabling the driving member 4 to be moved smoothly with arelatively small driving force. This enables the positional adjustmentsof the opening and closing operations of the blade members 3 (3A and 3B)to be carried out continuously with high resolution.

Moreover, a detecting portion (detecting means) 9, for detecting, eitherdirectly or indirectly, operation of the blade member 3, and acontrolling portion (not shown) for controlling the driving member 4(and, in particular, the current that is applied to the coils 6) inresponse to the detection output of the detecting portion 9, may beprovided in order to control variably the area within the opening 2A fortransmitting light that is not covered by the blade member 3. In thiscase, as described above, the driving member 4 moves smoothly, enablinghigh-resolution control.

An example of the detecting portion 9 in this case is a Hall elementthat detects the position of a magnet 5 in the driving member 4.Examples of the detecting portion 9 are not limited to such Hallelements, but may instead be a sensor for detecting position information(such as a linear encoder, or the like) attached to the blade member, asensor for detecting the brightness of the light that passes through theopening 2A (that is, the output of the imaging element), or the like.

Moreover, in controlling the driving of the driving member 4, ratherthan just controlling based on the detection portion 9, described above,a known control technique that is typically employed in electromagneticactuators may be used, such as feedback control for detecting a reverseelectromotive force that is produced in a damping coil that is providedin relation to a magnet 5, or feedback control of the group detectingthe state of conduction (current, voltage, pulse, etc.) of a coil 6.

In order to perform this control with higher accuracy, preferably themovement of the driving member 4 is limited to the axial direction (theX direction in the figures). In the examples depicted in FIG. 1 and FIG.3 , the movement of the driving member 4 may be limited to the axialdirection through limiting, in the axial direction (the X direction inthe figures) the movement of the supporting members 7 (the rollingelements 7A) through the supporting grooves 20A and the supportinggrooves 40A. Moreover, in the example depicted in FIG. 8 , the movementof the driving member 4 can be limited to the axial direction throughhaving the direction of the axles 7B1 of the rollers 7B be perpendicularto the axial direction (the X direction in the figures). In the exampledepicted in FIG. 9 , the movement of the driving member 4 can be limitedto the axial direction by having the direction of the shafts 7C be inthe axial direction (the X direction in the figures).

In contrast, in the examples depicted in FIG. 4 and FIG. 12 through FIG.14 , it is necessary to provide guiding means separately for limitingthe movement of the driving member 4, in order to limit the movement ofthe driving member 4 to the axial direction. It is possible to formthese guiding means through the provision of a guiding portion thatenables sliding along the axial direction, between a portion of thedriving member 4 and a portion (for example, a side wall 21) of the basemember 2.

Moreover, in the explanation set forth above, an example is depictedthrough moving-magnet driving wherein the magnets 5 are provided on thedriving member 4 side and coils 6 are provided on the base member 2side; however, the driving may instead be of a moving-coil drivingwherein magnets 5 are provided on the base member 2 side and coils 6 areprovided on the driving member 4 side. In this case, the provision ofback yolks 12 on the driving member 4 side makes it possible to producemagnetic attraction that acts between the driving member 4 and the basemember 2.

FIG. 16 depicts an example of another form of a driving member 4. Inthis example, the driving member 4 comprises a driving frame 40 that isable to move along a plane that is perpendicular to an optical axisthrough which an opening 2A passes, and a driving source (a lineardriving source) 50 for causing the driving frame 40 to undergo linearmotion in an axial direction, where the driving source 50 is coupled toa connecting portion 40T of a driving frame 40.

The driving source 50 comprises: a motor 51 and a rotational/linearmotion converting portion 53 for converting the rotation of the motor 51into linear motion. In the motor 51, the tip end of the rotary shaft 52thereof is born on a bearing 54A of an attaching member (a bracket) 54,where the driving source 50 is attached through an attaching member 54to the base member 2.

The rotational/linear motion converting portion 53, in the exampledepicted in FIG. 16 (a), comprises a male threaded portion 53A that isformed along the rotary shaft 52 of the motor 51 and a female screwmovable unit 53B that screws together with the male threaded portion53A. In this example, when the motor 51 drives the rotary shaft 52rotationally, the female screw movable unit 53B undergoes linear motionalong the rotary shaft 52, causing the driving frame 40, which iscoupled by the connecting portion 40T to the female screw movable unit53B, to undergo linear motion along the rotary shaft 52.

In the example depicted in FIG. 16 (b), the rotational/linear motionconverting portion 53 comprises a cam portion 53C that is formedhelically around the rotary shaft 52 of the motor 51. When the motor 51drives the rotary shaft 52 rotationally, the cam portion 53C is actuatedby the rotation of the rotary shaft 52, to cause the driving frame 40,which is coupled to the connecting portion 40T by the cam portion 53C,to undergo linear motion along the rotary shaft 52.

A stepping motor or a DC motor may be used as the motor 51 in thedriving source 50. When a stepping motor is used, it is possible tocause the linear motion of the driving frame 40 to move in stages(discontinuously). This enables the blade member 3, which is driven bythe driving member 40, to be moved quickly to an opening/closing statethat has been set, and to be held stably in that state. The drivingsource 50 is not limited to the motor 51 that has a rotary shaft 52, butinstead a piezoelectric element, or the like, may be used for thedriving source.

When a driving source 50 is used in this way, the opening/closing stateof the blade member 3 can be held in an arbitrary state in a non-poweredstate. When the blade driving device 1 is used as an iris device, it isnecessary to hold the opening/closing state of the blade member 3 in theblade driving device 1 constant at each of a variety of stages in orderto maintain the desired exposure level. With the driving source 50,after the blade member 3 has been moved to the position that enables thedesired exposure, it can be maintained in that state when in anon-powered state, making it possible to maintain the desired exposurewithout consuming battery power.

Example configurations of blade driving devices 1 that are equipped witha driving member 4 that comprises a driving source of 50 are depicted inFIG. 17 through FIG. 22 . The example depicted in FIG. 17 and FIG. 18 isan example that employees a driving member 4 and that comprises thedriving source 50 in the example depicted in FIG. 3 . The exampledepicted in FIG. 19 is an example that employees the structure depictedin FIG. 4 , as the structure for holding the rolling elements 7A, in theexample depicted in FIG. 17 . The example depicted in FIG. 20 is anexample that employees a driving member 4 and that the driving source50, in the example depicted in FIG. 11 . The example depicted in FIG. 21is an example that employees a driving member 4 and that the drivingsource 50, in the example depicted in FIG. 15 .

In these examples, one of the pair of driving frames 40 and 40 is causedby the driving source 50 to undergo linear motion in the X direction.The driving frame 40 is coupled with a coupling hole 10P of theoperating lever 10, which is born on the bearing portion 10A at thecenter of the shaft 20C of the base member 2, by a connecting portion (aprotruding portion) 40P. Through this, when the one driving frame 40moves to one side in the X direction, the other driving frame 40 movesto the other side in the X direction.

For the blade members 3 (3A and 3B), one blade member 3A is born througha rotary hole 3Q on a shaft 20P that passes through a through hole 40Qof the driving frame 40, and the other member 3B is supported, so as tobe able to slide in the X direction, through an elongated hole 3R on ashaft 20B that passes through a through hole 40Q of the driving frame40. Moreover, the blade members 3A and 3B are coupled to the endportions 10X and 10Y, respectively, of the operating lever 10 throughcoupling holes 3P. Through this, when the driving frame 40 is driven bythe driving source 50 to move along the X direction, one blade member 3Bmoves in the same direction as the X direction, while the other blademember 3A moves in the opposite direction along the X direction, whilerotating around the shaft 20P.

An opening limiting member 13 is provided in front of the opening 2A ofthe base member 2, where the opening area (the amount of exposure) whenthe blade member 3 is fully open is limited accurately by an opening 13Aof the opening limiting member 13. Moreover, through the movement of theblade member 3, described above, the blade members 3A and 3B willadvance into, or withdraw from, the opening 13A, so that the openingarea of the opening 13A (the amount of exposure) is adjusted variablywith high accuracy. Note that elongated holes 8P are formed followingthe rotation of the end portions 10X and 10Y the operating lever 10 inthe cover member 8.

In the example illustrated in FIG. 22 , magnets 5 for position detectionare provided in the driving frame 40, where coils 6 for positiondetection are provided at positions facing these magnets 5. Throughthis, when the driving frame 40 moves, driven by the driving source 50,the magnets 5 will move together therewith, and electric currents willflow in the coils 6, due to the electromagnetic induction caused by themovement of the magnets 5. The position of the driving frame 40 can bedetected through the currents that flow in the coils 6, making itpossible to control with good accuracy the movement of the blade member3, through feedback control of the driving source 50, based on thispositional detection.

FIG. 23 depicts a camera unit 100 that comprises a blade driving device1 wherein the driving member 4 is supported on the base member 2 throughsupporting members 7. The camera unit 100 comprises a lens drivingdevice 101 that is disposed behind the blade driving device 1 and isprovided with an imaging element 102 for capturing an image that isfocused on the lens by the lens driving device 101, disposed to the rearof the lens driving device 101. In the example in the figure, acontrolling portion 104 is provided on a circuit board 103 whereon theimaging element 102 is mounted, where the controlling portion 104outputs a control signal for controlling the driving member 4, based onbrightness detected by the imaging element 102. In this type of cameraunit 100, the provision of the thin blade driving device 1 that has asmall installation area enables the mounting space to be reduced,enabling the camera unit 100 as a whole to be made smaller.

Moreover, the use of the blade driving device 1 as a shutter deviceenables the provision of a shutter device able to achieve a high shutterspeed, with rapid responsiveness, through the smooth movement of thedriving member 4. The use of the blade driving device 1 as an irisdevice or an optical filter enables achievement of high resolutionbrightness control through smooth movement of the driving member 4.

Examples wherein operating levers (connecting members) are provided willbe explained in greater detail through FIG. 24 through FIG. 26 . In theexample depicted in FIG. 24 , the driving members 4 are supportedslidably on the base member 2 through rolling elements 7A (supportingmembers 7), where the pair of driving members 4A and 4B are linkedthrough the operating lever 10 that is born on the base member 2, sothat the pair of blade members 3A and 3B is also linked thereby.

In the example in the figures, the driving members 4 are movable elementof an electromagnetic actuator for linear driving made from magnets 5and coils 6, as a driving source for linear motion. The driving members4 comprise driving frames 40 and magnets 5 that are held on the drivingframes 40, where there is a pair of driving f 40, and a plurality ofmagnets 5 is held on each. While here an example is depicted wherein adriving source of the plurality of magnets 5 and a plurality of coils 6is provided, a single driving source may be provided instead. Thedriving source for the driving members 4 is not limited toelectromagnetic actuators as described above, but rather may employ anyof a variety of types of driving sources, such as piezoelectricactuators, electromagnetic plungers, and the like.

As illustrated in FIG. 25 , in the operating lever 10, a bearing portion10A is born on a shaft 2P that is provided on the base member 2, wherethe left and right end portions 10B and 10C are connected respectivelyto connecting portions 3A1 and 3B1 of blade members 3A and 3B. Moreover,connecting portions 4A1 and 4B1 in the driving members 4A and 4B areconnected to the left and right connecting portions 10D and 10E of theoperating lever 10. The blade member 3B has a guide hole 3B2 along thedirection of linear motion of the driving member 4, and the blade member3A has a guide hole 3A2. The guide hole 3B2 engages with a shaft 20B ofthe base member that passes through an escape hole 4B2 that is providedin the driving member 4B, where the guide hole 3A2 engages with theshaft 20P of the base member, which passes through the escape hole 4A2that is provided in the driving member 4A. The shafts 20B and 20Pprotrude from the base member 2 along the optical axis.

When the driving members 4A and 4B undergo linear motion along the Xdirection in mutually opposing directions, they move from the openedstate of the blade members 3A and 3B, illustrated in FIG. 25 (a) (whichis not a fully open state) to the blocked state of the blade members 3Aand 3B, depicted in FIG. 25 (b). At this time, through the connectingportions 4A1 and 4B1 of the driving members 4A and 4B, the operatinglever 10 rotates to cause the blade member 3B to undergo rotationalmovement around the shaft 20P, in relation to the linear motion of theblade member 3A, in the same direction as the driving member 4A,enabling the blade members 3A and 3B to open and close throughamplifying the amount of linear motion of the driving members 4A and 4B.

The opening 2A of the base member 2 is covered by an aperture plate 13that has a prescribed aperture shape 13A. Through this, when the blademember 3 is fully open, the aperture shape 13A of the aperture plate 13is open, making it possible to set accurately, through the apertureshape 13A, the amount of light that passes through when the blade member3 is fully opened. Moreover, through the overlap of the aperture shape13A and the blade members 3 (3A and 3B), the brightness of the lightthat passes therethrough can be adjusted accurately.

The example depicted in FIG. 26 is a modification of the exampledepicted in FIG. 25 . In this example, both blade members 3A and 3Bcomprise guide holes 3A2 and 3B2 that extend in the X direction, whereshafts 20P and 20B that protrude in the optical axial direction from thebase member 2 engage with these guide holes 3A2 and 3B2. Through this,the movement of the driving members 4 (4A and 4B) in the X directioncauses the blade members 3A and 3B to undergo linear motion along the Xdirection through the operating lever 10.

FIG. 27 through FIG. 35 depict more specific example configurations ofblade driving devices 1 according to examples according to the presentinvention. In the example depicted in FIG. 27 , the driving members 4are supported slidably on the base member 2 through rolling elements 7A(supporting members 7), where the pair of driving members 4A and 4B arelinked through the operating lever 10 that is born on the base member 2,so that the pair of blade members 3A and 3B is also linked thereby. Therolling elements 7A are supported, with the directions thereofconstrained by the supporting groups 40A of the driving frame 40 and thesupporting grooves 20A of the base member 2.

In the example in the figure, elastic members 30 are provided in theconnecting portions (linking portions) 10D and 10E that connect thedriving members 4 and the operating lever 10. The elastic member 30 hasthe function of suppressing connection play that is produced throughplay, provided between the connecting portions (protruding portions) 4A1and 4B1 that are provided on the driving member 4 side and the holeportions of the connecting portions 10D and 10E that fit therewith. Theprovision of play in the fit between the hole portions (elongated holes)of the connecting portions 10D and 10E and the connecting portions(protruding portions) 4A1 and 4B1 that are provided in the drivingmembers 4 enable the movement of the driving members 4 and the movementof the operating lever 10 to be linked smoothly. However, connectionplay is produced through this play, where this connection play producesmovement in the blade member 3, through, for example, shaking of thecamera, and through a change in the direction in which gravity acts dueto a change in the orientation of the camera, which is an encumbrancewhen attempting to control the opening/closing state of the blade member3 with good accuracy.

The elastic members 30 are attached, so as to bias the connectingportions (protruding portions) 4A1 and 4B1 that fit into the holeportions of the connecting portions (linking portions) 10D and 10E,within the hole portions. In this state, the connecting portions(protruding portions) 4A1 and 4B1 can move within the hole portions ofthe connecting portions 10D and 10E against the elastic forces of theelastic members 30 when driving forces are applied, but in a statewherein no driving forces are applied, they are pressed by the elasticforces of the elastic members 30, so as to prevent connecting play,causing the connecting portions 10D and 10E to be in a stationary statewithin the hole portions.

In the example in the figure, the elastic members 30 are wire members(rod members) that are supported on one end, where one end side of theelastic member 30 is engaged with an engaging portion 10F that isprovided on the periphery of the connecting portion 10D or 10E. Ifnecessary, an adhesive agent may be filled into the engaging portion10F. The adhesive agent may be selected as appropriate, such as anoptically curable adhesive agent, a thermally curable adhesive agent, orthe like. In the example in the figure, an example is depicted whereinthe elastic member 30 is a wire member (a rod member), but there is nolimitation thereto, but it may instead be a plate-shaped member (a platematerial). The material for the elastic member 30 may use a metal, aresin, or the like, that has elasticity.

Moreover, in the blade driving device 1, the provision of the elasticmembers 30 in the connecting portions 10D and 10E for the drivingmembers 4 and the operating lever (the connecting member) 10 makes itpossible to suppress connection play therebetween while smoothlytransferring the movement of the driving member 4 to the operating lever(the connecting member) 10. This suppresses the movement in the blademember 3 that is produced through camera shaking, and the like, or whenthe direction in which the force of gravity acts changes due to a changein orientation of the camera, making it possible to control the state ofopening/closing of the blade member 3 with good accuracy.

FIG. 30 shows the effects of providing the elastic members 30. Thevariability in the change of brightness (AV=log 2N2, where N is the irisvalue) as a function of the amount of movement of the blade is shown forthe case wherein elastic members 30 are provided in the connectingportions 10D and 10E (FIG. 30 (b)), and the case wherein no elasticmember 30 is provided (FIG. 30 (a)). Here the change in brightness iscalculated based on the brightness of the transmitted light in theopening 2A, which changes depending on the movement of the blade members3A and 3B.

When attempts are made to control, to the design values that areindicated by the solid line, the change in brightness through the amountof movement of the blades, if the elastic members 30 are not provided(referencing FIG. 30 (a)), then the change in brightness relative to theamount of movement of the blades has relatively large variabilitybetween the dotted line and the dash-dot line. In particular, thevariability is remarkable when the amount with which the blade is movedis large. In contrast, when the elastic members 30 are provided(referencing FIG. 30 (b)), the variability in the change in brightnessrelative to the amount of movement of the blades is kept small, as shownbetween the dotted line and the dash-dot line, and even if the amount ofmovement of the blade is large, the change in brightness is controlledby the amount of movement of the blades to be essentially the same asthe design values.

FIG. 31 and FIG. 32 depict another example of a blade driving device 1.In this example, connecting portions 4A3 and 4B3 that have hole portionsare provided in the driving members 4, and the operating lever 10 isprovided with protruding portions 10L and 10M that fit into the holeportions of the connecting portions 4A3 and 4B3.

The protruding portions 10L and 10M of the operating lever (theconnecting member) 10 are provided at intermediate positions between thebearing portion 10A and the end portions 10B and 10C, where theconnecting portions 4A3 and 4B3 into which these protruding portions 10Land 10M fit are provided in arm portions of the driving members 4A and4B. Moreover, the elastic members 30 are attached held on one endthereof in the hole portion peripheries of the connecting portions 4A3and 4B3 of the driving members 4A and 4B. In this way, the connectingportions 4A3 and 4B3 wherein the elastic members 30 are provided may beprovided on the driving member 4 side.

FIG. 33 through FIG. 35 depict another example configuration. The bladedriving device 1 in the figures comprises an operating lever 10 thatconnects the driving members 4 and the blade members 3 (3A and 3B). Thedriving member 4, which is equipped with a driving frame 40, issupported on the base plane 20 of the base member 2 through rollingelements 7A, supported so as to be able to move in a state wherein it isseparated from the base member 2. Given this, a linking portion 10X1,wherein connection play is suppressed, is provided between the drivingmember 4 and the operating lever 10.

The linking portion 10X1 links the driving member 4 and the operatinglever 10 through a magnetic force (magnetic attraction or magneticrepulsion). Explaining in more detail, the linking portion 10X1 isprovided with a magnet 5X that attracts or repels the magnet 5 that isprovided on the driving member 4.

The magnet (linking magnet) 5X that is provided in the linking portion10X1 is disposed facing, and adjacent to, the magnet (driving magnet) 5that is provided on the driving member 4, and causes the operating lever10 to undergo rotational motion, linked by the magnetic force (themagnetic attraction or magnetic repulsion) of the magnet 5X in relationto the linear motion of the driving member 4 (motion along the Xdirection in the figures). The attraction or repulsion of the magnet 5Xthat is provided in that the linking portion 10X1 in relation to themagnet 5 that is provided in the driving member 4 is set through theopposing magnetic poles of the magnet 5 and the magnet 5X being disposedwith opposite polarities or disposed with identical polarities. In theexample in the figures, the magnet 5X of the linking portion 10X1 islinked to the magnet 5 for driving, provided on the driving member 4;however, there is no limitation that thereto, but rather the magnet forlinking may be provided separately from the driving member 4.

In this example, the operating lever 10 has a linking portion 10X1provided on one end side thereof, and is connected to the blade member3B (3) on the other end side thereof, and is supported at anintermediate position between the one end side and the other end side.More specifically, a bearing portion 10A of the operating lever (theconnecting member) 10 is born on a shaft 2P of the base member 2, wherea linking portion 10X1 is provided on the end portion of one end side ofthe operating lever (the connecting member) 10 and the end portion 10Yon the other end side is connected to a connecting portion 3B1 of theblade member 3B.

Through this, when the driving member 4 (the driving frame 40) is movedin the X direction in the figures through driving of an electric currentin the coils 6, then, in coordination therewith, the operating lever 10rotates around the shaft 2P, where, through this rotation, one of theblade members 3B advances or withdraws on in relation to the opening 2A.Moreover, in the example in the figures, the other blade member 3A isattached as a single unit with the driving member 4 (the driving frame40), and thus through movement of the driving member 4 in the directionof X in the figures, advances or withdraws relative to the opening 2A.Here the operating lever (the connecting member) 10 has the function oflinking the movement of the two blade members 3A and 3B.

In the example in the figures, one of the blade members 3B is coupled toone end side of the operating lever 10 and the other blade member 3A isattached as a single unit to the driving member 4, but there is nolimitation thereto, but rather the blade member may be integrated with,for example, the operating lever 10 instead.

Because, in the blade driving device 1 depicted in FIG. 33 through FIG.35 , the driving members 4 and the operating lever 10 are linked throughmagnetic forces, it is possible to eliminate the connection play that isinevitable when the driving members 4 and the operating lever 10 arelinked mechanically. Consequently, this enables smooth operation ofboth, without producing connection play, when the end portions of theoperating lever 10, which move in arcs, are linked to the driving member4 that moves linearly.

Such a blade driving device 1 is able to cause the movable members tomove smoothly, and even when achieving a reduction in size and areduction in thickness of blade driving device 1, enables continuous andaccurate high-resolution control of the movement of the blade members 3(3A and 3B). Moreover, because the play in the linking portions betweenmembers is suppressed, the state of the opening/closing of the blademembers 3 (3A and 3B) can be controlled accurately. For example, thereis a limit to the sizes of the individual components with a camera in amobile telephone, and thus the aperture of the lens, or the like, issmall, so the effect of play when driving is large, with the risk thatit may become impossible to achieve the desired exposure control. Incontrast, with the blade driving device 1 according to the presentexample, the desired exposure control can be carried out moreappropriately due to the ability to control the state of opening/closingof the blade member 3 with better accuracy.

Moreover, because, in the blade driving device 1 that is depicted inFIG. 33 through FIG. 35 , the driving members 4 and the operating lever10 are linked through magnetic forces, there is no need for assemblingwith high accuracy for the positional relationships between the linkingportions 10X1 and the driving members 4, but the linking portions 10X1need merely be disposed within a range reached by the magnetic forces.Through this, the assembly of the driving device 1 can be carried outeasily, enabling an improvement in the manufacturability of the bladedriving device 1.

FIG. 36 through FIG. 42 depict other example configurations in relationto the driving source in a blade driving device 1 according to anexample according to the present invention. The blade driving device 1depicted in FIG. 36 and FIG. 37 comprises a base member 2, a blademember 3, and a driving member 4, and also comprises a driving source 50for driving the driving member 4, where the driving source 50 is similarto that of the examples described above in the point that it is madefrom magnets 5 and coils 6, but here an improvement in the driving forceis achieved through specifying the layout of the magnets 5 and the coils6.

FIG. 38 depicts an example configuration of the driving source 50(wherein (a) is an explanatory diagram that is a plan view and (b) is across-sectional view along the section X-X thereof). The magnet 5 of thedriving source 50 is provided with a unit magnetized portion 5U that ismagnetized along the optical axial direction (the Z direction in thefigures). In the example depicted in FIG. 38 , a single unit magnetizedportion 5U is formed from a single dipole magnet. Moreover, the coil 6of the driving source 50 comprises a coil portion 6U that has a pair oflinear parts 6L that generated a driving force through application of anelectric current thereto, where, in the example depicted in FIG. 38 ,two coil portions 6U are disposed above a single unit magnetized portion5U in the magnet 5. Note that here the linear part 6L need notnecessarily be formed so as to be completely straight, but may include abend part with a radius of curvature that is larger than that of anotherportion.

Additionally, in the driving source 50, two coil portions 6U are linedup along the driving direction (the direction of movement of the drivingmember 4) Xa, where two linear parts 6L, wherein the directions of theapplied currents, indicated by the dotted line arrows, are in theidentical direction, are disposed in relation to a single unitmagnetized portion 5U. To have the directions in which electric currentis applied to the two linear parts 6L over a single unit magnetizedportion 5U be the same direction the directions of coiling should be inmutually opposing coiling directions in the case of two adjacent coilportions 6U being connected in series; however the two coil portions 6Umay be connected individually (in parallel) instead, so as to have thedirections in which the electric currents are applied to the two linearparts 6L, over a single unit magnetized portion 5U, be in identicaldirections.

Such a driving source 50 makes it possible to produce a strong drivingforce through the application of an electric current to the two coilportions 6U, using the installation area for the unit magnetized portionof 5U effectively, through the lines of magnetic force that exit thenorth pole of the unit magnetized portion 5U and that arrive at thesouth pole thereof cut across, in identical directions, the two linearparts 6L to which electric currents are applied in identical directions.This makes it possible to achieve a relatively strong driving forcewhile reducing the space required for installing the driving source 50,making it possible to achieve miniaturization, enabling achievement ofan adequate driving force wherein the blade member can be controlled athigh speeds and with high resolution.

Moreover, when two linear parts 6L to which electric currents areapplied in identical directions are disposed in relation to a singleunit magnetized portion 5U, it is possible to increase the driving forcewithout changing the value of the electric currents that are applied(that is, without changing the amount of electric power consumed) whencompared to the case of disposing a single linear part of a coil portionfor each unit magnetized portion 5U. This makes it possible to bothincrease the driving force and conserve electric power in the drivingsource 50. This can increase the performance in the imaging operation ofa camera unit, or the like, while suppressing consumption of the batterypower, when the blade driving device that is driven by such a drivingsource 50 is equipped in a battery-powered mobile electronic device.

Because in such a blade driving device 1 the driving members 4 that aresupported, through rolling elements 7, in a state separated from thebase member 2 are driven by a driving source 50 that can produce arelatively high driving force, relative to the space for installing themagnet 5, this enables continuous operating control of the blade member3 with high resolution and high accuracy. Moreover, because the drivingsource 50 is disposed between the driving member 4, which moves within aplane, and a planer base member 2, this enables the blade driving device1 as a whole to be made thinner. Furthermore, because the coil portions6U of the coil 6 are disposed efficiently in relation to a single unitmagnetized portion 5U, miniaturization of the blade driving device 1 canbe achieved while still producing a large driving force.

In the example depicted in FIG. 36 and FIG. 37 , the supporting members7 (rolling elements 7A) are interposed between the base member 2 and thedriving member 4, and thus the driving member 4 is supported slideablyon the base member 2; however, here the supporting members 7 need notnecessarily be rolling elements (bearings) 7A, as illustrated in thefigure, but may instead be rollers 7B, shafts 7C, elastic members(springs or wires) 7D, or the like, as described above, wherein thedirection of rolling is constrained.

Other example configurations of driving sources 50 are depicted in FIG.39 and FIG. 40 . (a), (b), (c), and (d) in FIG. 39 are all magnets 5wherein unit magnetized portions 5U are arranged in a plurality alongthe driving direction Xa. A unit magnetized portion 5U, as describedabove, is a single magnetized unit that is magnetized along the opticalaxial direction (the Z direction in the figures), but when a pluralitythereof are arranged in a line, the magnet 5 may be formed througharranging a plurality of dipole magnets, each magnetized in the opticalaxial direction, in tight contact with each other, or by partiallymagnetizing within a single magnet, a magnet 5 may be obtained wherein aplurality of unit magnetized portions 5U are arranged in a line. In thiscase, a plurality of unit magnetized portions 5U may be arranged in aline in the driving direction Xa so that adjacent magnetic poles are ofmutually opposing polarities.

In the example depicted in FIG. 39 (a), two unit magnetized portions 5Uof a magnet 5 are arranged in a line along the driving direction Xa. Inrelation thereto, three coil portions 6U of a coil 6 are disposed overthe magnet 5. Given this, in relation to a single unit magnetizedportion of 5U, two linear parts 6L, having identical directions for thedirections in which the electric current is applied, are disposed inrelation to a single unit magnetized portion 5U.

In the example depicted in FIG. 39 (b), three unit magnetized portions5U of a magnet 5 are arranged in a line along the driving direction Xa.In relation thereto, four coil portions 6U of a coil 6 are disposed overthe magnet 5. Given this, in relation to a single unit magnetizedportion of 5U, two linear parts 6L, having identical directions for thedirections in which the electric current is applied, are disposed inrelation to a single unit magnetized portion 5U.

In the examples depicted in FIGS. 39 (a) and (b), if the number of unitmagnetized portions 5U of the magnet 5 is defined as N, then the numberof coil portions for the coil 6 will be N+1. For the number N of theunit magnetized portions 5U in the magnet 5, an appropriate numberthereof may be arranged depending on the amount of movement of thedriving member 4 along the driving direction Xa, and depending on thedriving force that is to be set. In these examples, the width of thearray of magnets 5 can be reduced, in relation to the width of the arrayof coils 6, and a desired driving force can be produced.

In the example depicted in FIG. 39 (c), three unit magnetized portions5U of a magnet 5 are arranged in a line along the driving direction Xa.In relation thereto, two coil portions 6U of a coil 6 are disposed overthe magnet 5. Given this, in relation to a single unit magnetizedportion of 5U that is disposed in the center, two linear parts 6L,having identical directions for the directions in which the electriccurrent is applied, are disposed in relation to a single unit magnetizedportion 5U.

In the example depicted in FIG. 39 (d), four unit magnetized portions 5Uof a magnet 5 are arranged in a line along the driving direction Xa. Inrelation thereto, three coil portions 6U of a coil 6 are disposed overthe magnet 5. Given this, in relation to a single unit magnetizedportion of 5U, other than at the two end portions, two linear parts 6L,having identical directions for the directions in which the electriccurrent is applied, are disposed in relation to a single unit magnetizedportion 5U.

In the examples depicted in FIGS. 39 (c) and (d), if the number of unitmagnetized portions 5U of the magnet 5 is defined as N, then the numberof coil portions for the coil 6 will be N−1. For the number N of theunit magnetized portions 5U in the magnet 5, an appropriate numberthereof may be arranged depending on the amount of movement of thedriving member 4 along the driving direction Xa, and depending on thedriving force that is to be set. In these examples, the width of thearray of coils 6 can be reduced, in relation to the width of the arrayof magnets 5, and a desired driving force can be produced.

FIG. 40 depicts an example wherein the driving source 50, depicted inFIG. 39 , is installed. A driving source 50 such as depicted in FIG. 39can be provided in a plurality in relation to the base member 2. In theexample in the figure, a driving source 50 is disposed on both the leftand the right sides of the opening 2A, to drive the pair of drivingmembers 4A and 4B in mutually differing directions; however, there is nolimitation thereto, but rather these may be installed as appropriate.

Other example configurations of driving sources 50 are depicted in FIG.41 and FIG. 42 . The examples depicted in FIGS. 41 (a) and (b) aremodified examples of the examples depicted in FIGS. 39 (c) and (d)(examples wherein the numbers of coil portions are N−1 in relation tothe numbers N of unit magnetized portions 5U). In the example depictedin FIG. 41 (a), three unit magnetized portions 5U of the magnet 5 arearranged in a line along the driving direction the Xa, and two coilportions 6U of the coil 6 are arranged in a line over the magnet 5, sothat, for each single unit magnetized portion 5U, two linear parts 6L,having identical directions for the directions in which the electriccurrent is applied, will be disposed in relation to a single unitmagnetized portion 5U, except for at both end portions of the magnet 5.In the example depicted in FIG. 41 (b), four unit magnetized portions 5Uof the magnet 5 are arranged in a line along the driving direction theXa, and three coil portions 6U of the coil 6 are arranged in a line overthe magnet 5, so that, for each single unit magnetized portion 5U, twolinear parts 6L, having identical directions for the directions in whichthe electric current is applied, will be disposed in relation to asingle unit magnetized portion 5U, except for at both end portions ofthe magnet 5.

Moreover, in the examples depicted in FIGS. 41 (a) and (b), the areasfor the surfaces, of the unit magnetized portions 5U, that face the coil6 are reduced at both end portions of the magnet 5, structured so thatthe areas at both end portions of the magnet 5 will be smaller than theareas in the other portions. In the example in the figures, when theareas of the unit magnetized portions 5U other than at both end portionsof the magnet 5 are defined as a, the areas of the unit magnetizedportions 5U at both end portions of the magnet 5 will be a/2. In theseexamples, the area of the surface of the magnet 5 that faces the coil 6will have a total area of south poles in the unit magnetized portion 5Uthat is equal to the total area of the north poles in the unitmagnetized portions 5U. Structuring in this way can reduce the width ofthe array of magnets 5 and the width of the array of coils 6 in thedriving source 50, and can also produce a driving force that issufficient because the linear parts 6L in the coil 6 are arrangedefficiently in relation to the unit magnetized portions 5U in the magnet5.

FIG. 42 depicts an example wherein the driving source 50, depicted inFIG. 41 , is installed. A driving source 50 such as depicted in FIG. 41can be provided in a plurality in relation to the base member 2. In theexample in the figure, a driving source 50 is disposed on both the leftand the right sides of the opening 2A, to drive the pair of drivingmembers 4A and 4B in mutually differing directions; however, there is nolimitation thereto, but rather these may be installed as appropriate.

In the blade driving devices 1 according to all of the examplesdescribed above, back yolks 12 are provided, and the positions of thedriving member 4 when driven (when an electric current is applied) andwhen not driven (when no electric current is applied) are held by themagnetic force of the magnet 5 that acts on the back yoke 12. FIG. 43through FIG. 46 show the positional relationships between the back yoke12 and the magnet 5 that is provided on the driving member 4 (where (a)is a cross-sectional explanatory diagram and (b) is a planar explanatorydiagram).

As illustrated in FIG. 43 , providing a back yoke 12 on one side of theopening 2A in relation to the position of the driving member 4 when notdriven makes it possible to move and hold the driving member 4 on oneside of the opening 2A through the magnetic force of the back yoke 12and the magnet 5 when the driving member 4 is driven. Conversely, itmakes it possible to move and hold the driving member 4 on one side ofthe opening 2A through the magnetic force of the back yoke 12 and of themagnet 5 when the driving member 4 is not driven.

Moreover, as depicted in FIG. 44 , the provision of back yolks 12 onboth sides of the opening 2A in relation to the position of the drivingmember 4 when not driven enables holding of the driving member 4 at bothsides of the opening 2A (on one side or the other side) through themagnetic force of the back yoke 12 and the magnet 5 when the drivingmember 4 is driven. Moreover, conversely, it makes it possible to holdthe driving member 4 on both sides of the opening 2A (on one side andthe other side) through the magnetic force of the back yoke 12 and themagnet 5 when the driving member 4 is not driven.

Moreover, as illustrated in FIG. 45 , the driving member 4 can be heldalong a direction that is perpendicular to the optical axis O by themagnetic force of the back yoke 12 and the magnet 5 when driven or whennot driven, and as depicted in FIG. 46 , the driving member 4 can beheld along the direction of the optical axis O by the magnetic force ofthe back yoke 12 and the magnet 5 when driven or when not driven. Whenthe driving member 4 is held along the optical axis O direction, byholding at the position of essentially the center of gravity, includingthe blade member 3, the driving member 4 can be held stably, withoutbeing off-angle.

Given this, in addition to the driving member 4 of the blade drivingdevice 1 of the examples described above being held by the magneticforces described above, or instead of being held by the magnetic forces,it may be held by a spring force. In particular, in holding by a springforce, the position of the driving member 4 when not driven may be heldin a neutral position. FIG. 47 depicts a case wherein the driving member4 is held on the base member 2 by a spring force (wherein (a) is across-sectional explanatory diagram and (b) is a planar explanatorydiagram). In this example, the spring 14 is disposed at an angle inrelation to the optical axis O, so that the driving member 4 will beheld elastically along both a direction that is perpendicular to theoptical axis O and also along the direction of the optical axis O.Moreover, there is no limitation to the example in the figure, butrather a spring 14 may be disposed along the optical axis O to hold thedriving member 4 elastically in the direction of the optical axis O, anda spring 14 may be disposed along a direction that is perpendicular tothe optical axis O, to hold the driving member 4 in a direction that isperpendicular to the optical axis O.

Moreover, in the blade driving device 1 in the examples described above,driving of the driving member 4 was controlled through detecting meansfor detecting the operation of the driving member 4 or the blade member3, where examples were depicted wherein a Hall element 9, or the like,was provided as the detecting means; however, detecting means such asdescribed below may be employed instead.

The detecting means depicted in FIG. 48 (wherein (a) is across-sectional explanatory diagram and (b) is a planar explanatorydiagram) are an optical sensor 15 for detecting optically the operationof the driving member 4 or the blade member 3. The optical sensor 15 maycomprise, for example, a photodetecting portion 15 b for detecting lightemitted from the light emitting portion 15 a, wherein a pair of opticalsensors 15 is disposed at both sides, in the direction of movement ofthe driving member 4 that is a direction of movement that isperpendicular to the optical axis O, wherein the end portions of thedriving member 4 are disposed at positions that block the light, todetect the operating position of the driving member 4 through thedifference in the outputs of the pair of optical sensors 15.

The detecting means depicted in 49 may each use coils. In the exampledepicted in (a), a coil 16 for detection, which is separate from thecoil 6 for driving, is disposed facing the magnet 5 that is provided onthe driving member 4. This enables the operating position of the drivingmember 4 to be detected through the induced electromotive force that isproduced in the detecting coil 16. In the example depicted in (b), adamping coil 17 that is separate from the coil 6 for driving is disposedfacing the magnet 5 that is provided on the driving member 4. Throughthis, the operating position of the driving member 4 can be detectedthrough the conduction of the damping coil 17. Moreover, the operatingposition of the driving member 4 or of the blade member 3 can also bedetected through the state of conduction in the coil 6 for driving thatforms the driving source.

FIG. 50 depicts a more specific example configuration of a blade drivingdevice 1. Some or all portions of the example configuration depicted inFIG. 50 can be applied to all of the example configurations that areprovided with an operating lever (the connecting member) 10, describedabove. In the example in the figure, the bearing portion 10A of theoperating lever (the connecting member) 10 is provided with an elasticmember 31 for preventing support play.

The bearing portion 10A of the operating lever 10 is born on a shaft 2P(20C) of the base member 2, where the operating lever 10 is rotated,around the shaft 2P (20C), through driving of the driving member 4. Theaxle hole of the bearing portion 10A and the shaft 2P (20C) fit togetherto enable the operating lever 10 to rotate smoothly, but given theslight gap, due to tolerance error, there may be play in the movement ofthe operating lever 10. Moreover, even if the shaft 2P is fitted intothe axle hole of the bearing portion 10A with a fitting tolerance errorthat keeps the play to a minimum, still the amount of play may exceed atolerable range due to changes over time caused by repeated operation.At this time, the play of the operating lever 10 will not only become afactor that will interfere with the smooth operation of the blade member3, but will also become a factor that interferes with highly accuratecontrol of the blade operation (control of the light that passes throughthe opening).

The elastic member 31 that is provided in the bearing portion 10A of theoperating lever 10 elastically biases the shaft 2P (20C) to one side ofthe axle hole of the bearing portion 10A, to prevent play of theoperating lever 10 while supporting the smooth rotation of the operatinglever 10. The provision of such an elastic member 31 enables a reductionin the time required in the assembly procedures, and prevents the play,due to changes over time accompanying repeated operation, from exceedingthe tolerable range that is set initially.

The elastic member 31 can be structured through a wire that is supportedon one end, and, as illustrated, the elastic member 31 is caused tocontact the side face of the shaft 2P (20C) that is born in the bearingportion 10A, so that the biasing force of the elastic member 31 willbias toward the center of the axle hole of the bearing portion 10A, withone and 31A of the elastic member 31 secured at the periphery of thebearing portion 10A. In the example in the figure, a portion of theshaft 2P (20C) is exposed through the provision of a stepped portion inthe bearing portion 10A, and the elastic member 31 is caused to contactthe side face of the shaft 2P (20C) that is exposed.

In the example in the figure, the elastic members 31 are provided in thebearing portions 10A, and, additionally, elastic members 30 forsuppressing connection play, in the same manner as in the exampleconfiguration depicted in FIG. 29 , are provided also at the connectingportions 10D and 10E of the operating lever 10 to which the connectingportions 40P (4A1 and 4B1) of the driving member 4 are connected. Inthis way, the provision of both the elastic member 31 for preventingsupport play and the elastic members 30 for preventing connection playenables highly accurate control of the movement of the blade member 3that is operated through the operating lever 10. The use of the exampleconfiguration depicted in FIG. 50 enables fine control of the blademember 3 in the blade driving device 1, and enables high accuracyadjustments of the optical characteristics, such as the iris, thereof.

FIG. 51 depicts a camera unit 100 that is provided with a blade drivingdevice 1 as described above. The blade driving device 1 that isinstalled in the camera unit 100 can function as an iris unit, a shutterunit, a filter switching unit, or the like. The camera unit 100 isequipped with a lens driving device 101, an imaging element 102, and thelike. The imaging element 102 can function also as detecting means, asdescribed above. In this case, the operation of the driving member 4 orthe blade member 3 is detected by the imaging element 102 as the amountof light that passes through the opening 2A, and the operation of thedriving member 4 is controlled by this detection output.

In the example in the figure, a controlling portion 104 is provided on acircuit board 103 whereon the imaging element 102 is mounted, where thecontrolling portion 104 outputs a control signal for controlling thedriving member 4, based on brightness detected by the imaging element102. In this type of camera unit 100, the provision of the thin bladedriving device 1 that has a small installation area enables the mountingspace to be reduced, enabling the camera unit 100 as a whole to be madesmaller.

When the blade driving device 1 is used as a shutter unit, the smoothmovement of the driving member 4 enables achievement of a high shutterspeed with quick responsiveness. When the blade driving device 1 is usedas an iris unit or a filter switching unit, the smooth movement of thedriving member 4 enables achievement of high resolution brightnesscontrol.

FIG. 52 depicts a mobile electronic device 200 wherein the camera unit100, described above, is installed. The camera unit 100 that enablesachievement of miniaturization reduces the space for installation thatis occupied in the mobile electronic device 200, contributing to furtherminiaturization and thickness reduction the mobile electronic device200. Camera units 100 of recent years have tended to use imagingelements with high sensitivity, so adjustments to the exposure throughiris devices has been indispensable in obtaining clear images underbright imaging conditions, such as when capturing images outdoors. Thecamera unit 100 that is provided with the blade driving device 1according to an example according to the present invention can bemounted in a mobile electronic device 200, making it possible to obtaina clear adjustment with the appropriate exposure, despite being a cameraunit 100 that is installed in a small mobile electronic device 200.

While examples according to the present invention were described indetail above, referencing the drawings, the specific structures thereofare not limited to these examples, but rather design variations within arange that does not deviate from the spirit and intent of the presentinvention are also included in the present invention. Moreover, insofaras there are no particular contradictions or problems in purposes orstructures, or the like, the technologies of the various examplesdescribed above may be used together in combination.

The invention claimed is:
 1. A blade driving device comprising: abasemember comprising an opening; a blade member that operates so as toadvance into the opening or withdraw from the opening; a driver movingwithin a plane that is perpendicular to an optical axis that passesthrough the opening, the driver including a lever, a magnet and a coilfor driving the blade member, one of the magnet and the coil beingstationary relative to the base member, and the other of the magnet andthe coil being movable relative to the base member to drive the blademember; when the other of the magnet and the coil is moved relative tothe base member to drive the blade member, the lever rotates and theblade member is driven; and a supporting member that supports thedriver, wherein the magnet comprises a magnetized portion beingmagnetized along the optical axis and the coil comprises a coil portionincluding a pair of linear parts, the pair of linear parts producing adriving force through an application of an electric current when theelectric current is disposed over the magnet, where the pair of linearparts having the electric current applied in identical directions aredisposed in relation to at least the magnetized portion.
 2. The bladedriving device as set forth in claim 1, wherein the supporting member isprovided between the base member and the driver, to at least one ofslidably or elastically support the driving member in a state separatedfrom the base member, wherein the supporting member comprises a rollingelement that supports sliding of the driver in respect to the basemember, and is rolled by the movement of the driver.
 3. The bladedriving device as set forth in claim 2, wherein: the rolling element isheld, so as to enable rolling, in a prescribed position within aretaining portion that is provided on the driving member or the basemember.
 4. The blade driving device as set forth in claim 1, wherein:the blade member is provided in a pair thereof.
 5. The blade drivingdevice as set forth m claim 4, wherein: the driver is a single unit, andis provided with an operating mechanism operating the pair of blademembers in mutually opposing directions through an operation of thedriver in one direction.
 6. The blade driving device as set forth inclaim 1, comprising: a detector detecting operation of the blade member,either directly or indirectly; and a controller controlling the driver.7. The blade driving device of claim 1, comprising: two blade membersthat operates so as to advance into the opening or withdraw from theopening, wherein the lever that connects the two blade members, thedriver includes two voice coil members arranged symmetrically withrespect to a center of rotation of the lever in a plan view.